Mirage Mediation of SupersymMirage Mediation of Supersymmetry Breaking: metry Breaking: Phenomenology aPhenomenology a

nd Cosmologynd Cosmology

Masahiro Yamaguchi

(Tohoku University)

Sep. 25, 2008 @TeVPA, Beijing

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Talk PlanTalk Plan

Introduction and motivation

New Theoretical developments in SUSY

Mirage Mediation

Moduli/Gravitino problem and a solution

Summary

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Call for Particle Physics beyond Standard Model

Stabilization of Weak Scale

Neutrino Masses and Mixing

Components of Universe(dark energy)

dark matter

baryons (baryogenesis)

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Low-Energy Supersymmetry

Promising candidate for Beyond-Standard-Model

Symmetry between bosons and fermions Thanks to difference of statistics, quantum corrections te

nd to cancel (at least partially). no quadratic divergence in Higgs mass stabilizes weak scale due to (broken) symmetry

Unification of gauge forces in SUSY

Lightest superparticle (LSP)stable (if R-parity conservation), and a natural dark matter candidate

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Even if SUSY is a correct solution, there are still a wide variety of possibilities.

Example: SUSY breaking scale and gravitino mass Gravitino Mass m3/2 ~ F/MPl

Sparticle Mass m ~F/M (M: messenger scale) M~105 GeV—1020 GeV m/m3/2 ~ M/MPl

(m3/2 >> 100TeV split SUSY?) m3/2 ~ 100TeV anomaly mediation mirage mediation (this talk) m3/2 ~ 1 TeV gravity mediation m3/2 << 1 TeV gauge mediation

Phenomenology/Cosmology are different for a different value of gravitino mass.

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LHC (Large Hadron Collider) Experimentpp collider at CERNCenter of mass energy =14 TeV Starts in 2008!Expects new physics discovery at TeV scale

New Ideas will be tested at LHC!

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2. Recent Theoretical Developments in 2. Recent Theoretical Developments in SUSYSUSY

Meta-Stable SUSY Breaking Vacuasimple realization of SUSY breaking

Moduli Stabilization in Superstring Theory (KKLT) First realization of stabilization of all

moduli/dilaton based on flux compactification

+ non-perturbative effects (e.g. gaugino condensation)

Intriligator, Seiberg,& Shih ‘06

Kachru,Kallosh,Linde&Trivedi ‘03

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Meta Stable SUSY Breaking Vacua

Difficulty of dynamical SUSY breakingchiral gauge theory Witten index(broken) R-symmetry

model building possible, but very non-trivial

New possibilitySUSY preserving in true vacuum SUSY is broken in meta-stable vacuum (with long life time)

This is realized in many generic models such as SUSY QCD with massive flavors.

Intriligator, Seiberg,& Shih ‘06

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Advantages

SUSY breaking occurs in rather a generic set-up.

Model building becomes easier, in particular, in gauge mediation.

No light R-axion cosmologically safer

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Moduli Stabilization

String Theorymoduli fields: size and shape of extra dimensionsdilaton field: string coupling constant

Moduli stabilizationFlat directions at tree level

gauge couplings, masses not fixed new long range force ( disaster)

Some non-trivial effects are needed to stabilize moduli/dilation long standing problem since 80’s

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New Mechanism: Flux Compactifications

Higher rank tensors in string theory e.g. type IIB superstring

Superpotential

Switch on fluxes generation of superpotential for shape moduli stabilizing shape moduli (and dilaton)

2 form field :

3 form field strength :

shape (or complex) moduli

Giddings-Kachru-Polchinski ‘02

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KKLT Set-Up

Overall moduli (Kaehler moduli) not yet stabilized

One needs further steps

1) non-perturbative effects for Kaehler moduli

(known effects, e.g. gaugino condensate)– Kaehler moduli stabilized– Anti de-Sitter space with SUSY unbroken

2) Uplifting by some SUSY breaking source

(e.g. anti-D brane/ dynamical SUSY breaking)

Minkowski space with SUSY breaking

Kachru-Kallosh-Linde-Trivedi 03

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3. Mirage Mediation3. Mirage Mediation

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Implications to Low-E SUSY

Original Motivation of KKLT: realization of dS vacuum in string theory

Simple KKLT set-up can also provide a new mediation mechanism of SUSY breaking.

Sparticle mass spectrum mixture of moduli and anomaly mediation = mirage mediation

Choi-Falkowski-Nilles-Olechowski-Pokorski 04,05Endo-MY-Yoshioka 05Choi-Jeong-Okumura 05

and subsequent papers

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Phenomenology with KKLT-type model

SUSY breaking sector added to uplift potentialSUSY breaking by moduli is sub-dominant

Overall SUSY breaking characterized by gravitino mass:

little hierarchy among masses: Moduli T gravitino 　　　 sparticles 　　　 (compensator ) FT~m3/2

2/mT << F= m3/2 mT >> m3/2 >> msoft

~104 TeV ~100 TeV ~ 1 TeV

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Gaugino Masses

@GUT scale

moduli+anomaly mediation: two contributions comparable

Consider SM on D7 brane

Gauge kinetic function

Gaugino Mass

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Gaugino Masses

For R~35 (KKLT),

M1: M2: M3~1 : 1.3: 2

cf.

M1: M2: M3~1: 2: 7

(mSUGRA)

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Mirage Mediation

RG properties:

Gaugino masses are unified at a mirage scale.

Similar argument

to scalar masses

Choi, Jeong, Okumura 05

from Lebedev, Nilles, Ratz 05

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General Features of Mirage Mediation

Compressed Sparticle Mass Spectrumsmall parameter (~M1) small gluino mass/ RGE

LSP(lightest superparticle): neutralino admixture of gauginos and higginos 　 (somewhat model dependen

t)

stau: tends to be light

Mass Spectrum is very different from mSUGRA (CMSSM) gauge mediation & anomaly mediation

Testable at future collider experiments (LHC/ILC)

Endo-MY-Yoshioka 05Choi-Jeong-Okumura 05

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Thermal Relic Neutralino

Relic Abundance Detection Rate (SI)

Choi-Lee-Shimizu-Kim-Okumura 06

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4. Potential Problem and Resolution4. Potential Problem and Resolution

Cosmological Moduli ProblemPotential minimum during inflation is in general different from true minimum.

displacement from true minimum

Damped coherent oscillation will dominate energy density of the universe

Moduli are heavy. lifetime shorter than 1 sec. no entropy crisis

But …….

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Life is not so easy!

Moduli-induced Gravitino Problem

Moduli decay into gravitino pair with Br.~0.01

Dangerous decay chain:

moduli gravitini sparticles LSPs

Overabundance of LSPs

Gravitino mass must beheavier than ~106 GeVto escape overclosureconstraint. (wino case)

Even severer constrainton gravitino mass for other neutralino case

Endo,Hamaguchi,Takahashi 06Nakamura,MY 06cf. Joichi-MY ‘95

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Resolutions

Modifications of moduli potentialno shift of minimum during inflation

e.g. symmetry enhancement

Concrete realization of this idea??

Lighter LPSs Nakamura-Okumura-MY ‘08

Model with axino LSP

solves the LSP-overabundance problem

and also mu/B problem in SUSY

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Cosmology Highlightaxino dark matter

Axino can be dark matter when mass ~0.1 GeV.

Axinos are produced energitically.

Free-streaming length

O(0.1) MPc.

Maybe some implication to (small) scale structure

axino abundance for typical NLSP

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Phenomenology Highlights

Neutralino NLSP decay (to Axino) decay length bino-like NLSP: very long higgsino-like NLSP displaced vertex to h/Z: specutacular signals at LHC!

Sparticle Mass Spectrum general mixture of Moduli/Gauge/Anomaly mediation Mirage unification still holds for gaugino masses. This is not the case for scalar masses.　　　　　　　　　　　　　　　　　　　　

Everret et al ‘08Choi et al, in preparation

Nakamura,Okumura,MY08, and work in progress

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SummarySummaryLow-Energy SUSY: promising candidate for beyond SM discovery at LHC ?

SUSY Pheno/Cosmology: sensitive to mediation mechanism of SUSY breaking

New Developmentsmeta-stable SUSY breaking vacuagauge mediationmoduli stabilization a la KKLT mirage mediation

Models of mirage mediation consideredSparticle Masses (anomaly+moduli mediation)Thermal Relic Neutralinos can be DMPotential moduli/gravitino problem axino DM?